1. Field
One embodiment of the present invention relates to a scanning type exposure apparatus which projects and exposes an image of a first object (such as a mask and a reticle) on a second object (such as a substrate), a method of manufacturing a micro-device by using the scanning type exposure apparatus, a mask used for the scanning type exposure apparatus, a projection optical apparatus which projects the image of the first object on the second object, and a method of manufacturing the mask used for the scanning type exposure apparatus.
2. Description of the Related Art
For example, when a semiconductor device or a liquid crystal display device is manufactured, there is used a projection exposure apparatus which projects a pattern of a mask (such as a reticle and a photomask) on a plate (such as a glass plate and a semiconductor wafer) coated with photo-resist via a projection optical system. Conventionally, a projection exposure apparatus (stepper) which collectively exposes each pattern of reticle onto each shot region on the plate by the step and repeat system, has been frequently used. In recent years, instead of using one large projection optical system, there is proposed a step-and-scan type projection exposure apparatus in which a plurality of small partial projection optical systems comprising unit magnification are arranged in a plurality of rows at a predetermined interval along a scanning direction, and which exposes a pattern of a mask on a plate by the respective partial projection optical systems while scanning the mask and the plate.
In the above described step-and-scan type projection exposure apparatus, an intermediate image of a pattern on a mask is once formed by a catadioptric optical system constituted by including a reflecting prism, a concave mirror, and respective lenses, and the intermediate image is then exposed once more by a catadioptric optical system of another stage so that an unmagnified(unit) erecting image of the pattern on the mask is formed on a plate.
In recent years, a plate has been increasingly enlarged, and a plate comprising a size exceeding 2 m square has been used. Here, when a large-sized plate is exposed by using the above described step-and-scan type exposure apparatus, the size of a mask is also increased because the partial projection optical system has unit magnification. As the size of a mask is increased, the planarity of the mask substrate also needs to be maintained, which results in a further increase in the cost of the mask. Masks corresponding to four to five layers are needed in order to form an ordinary TFT part, and hence a large cost is required. It is disclosed by, for example, U.S. Pat. No. 6,512,573, a projection exposure apparatus which is capable of reducing the size of a mask by adopting enlargement magnification as the magnification of the projection optical system.